Method of excavating to form or enlarge a waterway

ABSTRACT

A method of forming or enlarging an underwater basin or body of water having an earth bank with chippable material such as brush, roots, and trees growing at the bank wherein earth is dredged from the bank, collected, and removed as an earth-water slurry. The chippable material is reduced to fragments and also introduced to the slurry for removal with the excavated earth.

United States Patent [1 1 Smith Feb. 25, 1975 [54] METHOD OF EXCAVATING TO FORM 0R 3,094,795 6/1963 Schmidt 37/67 T w Y 3,521,387 7 1970 Degelman ENLARGE 'W ER A 3,683,522 8/1972 Rousseau et al........

[76] inventor: Leward N- Smith, 491 Somerset 3,738,029 6/1973 Harmon 37/66 Saginaw, Remus, Mich, 48603 22 Fl I 23 1973 FOREIGN PATENTS OR APPLICATIONS 1 y 657,576 3/1938 Germany 37/67 [21] Appl. No; 381,705 1,574,816 6/1969 France 37/2 R Related US. Application Data P E Crff d D C d rtmary xammerl or row er [62] 221538 1972 Attorney, Agent, or Firm-Learman & McCulloch [52] US. CL... 37/195, 37/2 R, 37/189, [57 ABSTRACT 56/9, 144/3 D, 144/34 B, 144/309 AC,

- 241/101], 271/278 R A method of forming or enlarging an underwater basm [51] im. Cl ..E02f ms or body of Water having an earth bank with chippable [58] Field of Search M 37/67 58 64 66, 65, material such as brush, roots, and trees growing at the 37/2 95 1 9 90. 5 9. 144 34 B 309 bank wherein earth is dredged from the bank, COl- A 4 277L282 lected, and removed as an earth-water slurry. The chippable material is reduced to fragments and also [56] References Cited introduced to the slurry for removal with the exca- UNITED STATES PATENTS vaed earth 2,830,389 4/1958 Simpson 37/67 X 5 Claims, 9 Drawing Figures PATENTEB FEBZ 5 I975 SHEET 2 OF 4 PATENTED FEBZSHEFS SHEET 3 [1F 4 PATENTEUFEBZSIWS I SHEET u 0F 4 METHOD OF EXCAVATING TO FORM OR ENLARGE A WATERWAY This is a division, of application Ser. No. 221,538, filed in the U.S. Pat. Office on Jan. 28, I972 now U.S. Pat. No. 3,777,375.

FIELD OF THE INVENTION This invention relates to a dredging method which is employed to excavate and remove earth from below the surface of the water in a lake, stream, or the like to be dug or enlarged, and more particularly to a method wherein an upper layer of earth is removed while cutting trees, brush and root systems at the banks of the waterway into small chips and fragments so that they can be removed with the earth in the form of a slurry.

BACKGROUND OF THE INVENTION ries ago, occupied many areas which today are swamps or swales. Over hundreds of years, such lakes, through atrophy, have ceased to exist and become overgrown with brush, trees and the like.

' With ever-increasing land values, it has become increasingly important to develop waterfront property at a reasonable price. Such water-front property can be provided at low prices, if such bogs or swamps can be economically cleaned out to previous depths to again provide lakes similar to those which existed hundreds of years ago. i v

The root system associated with trees and brush, growing in such a swamp or bog, is generally relatively shallow. It is not possible to economically dredge an area which is overgrown with such a root mass, utilizing the apparatus disclosed in the Schmidt and Milne pa tents, because theroot masses continually wrap around the rotary cutterhead to prevent further removal of earth and plug the suction material removing system. Thus, it is necessary to repeatedly stop the machine and clear the cutterhead and suction system. In addition to being time-consuming, the physical removal of the roots from the cutterhead is particularly difficult to manually accomplish since the machine is operating in water or a relatively soft bog where thhrer is no footing. Moreover, pieces of the roots frequently become wedged in the suction pipe which removes the material from the cutterhead and prevent further dredging.

Accordingly, it is an object of the present invention to provide a method of dredging which includes the steps of reducing partially submerged roots, and above ground trees and brush to chips and simultaneously excavating earth and removing the earth and chipped material to a remote location in the form of a slurry.

It is yet another object of the present invention to provide a method for economically reclaiming atrophied lakes and making new shoreline available at reasonable prices.

Other objects and advantages of the present invention become apparent to those of ordinary skill in the art as the description thereof proceeds.

SUMMARY OF THE INVENTION A method of enlarging an underwater basin or body of water having an earth bank with trees, brush. and roots growing on it wherein a material collecting dredge element is moved in a generally horizontal path below water level to collect earth material from the bank and a rotating chipper disc having knife mechanism for reducing the trees, brush and roots to chips and fragments is also moved in a horizontal path at water level. Both the chipped material and earth material are removed by the dredge in slurry form.

The present invention may more readily be described by reference to the accompanying drawings, in which:

FIG. 1 is a side elevational view illustrating apparatus for practicing the method of the present invention;

FIG. 2 is a top plan view of the apparatus illustrated in FIG. 1;

FIG. 3 is a fragmentary, front perspective view illustrating the chipping assembly only;

FIG. '4 is a side elevational view of the chipping disc only;

FIG. 5 is an enlarged, sectional plan view taken on about the line 5-5 of FIG. 4;

FIG. 6 is a front end elevational view of a chipping knife only;

FIG. 7 is a side elevational view thereof;

FIG. 8 is an opposite end elevational view thereof; and

FIG. 9 is a perspective view of one of the cutting knives.

DESCRIPTION OF THE PREFERRED EMBODIMENT The method of the present invention is particularly well adapted for clearing a bog or swamp which is overgrown with brush and trees 10, having a shallow root system 12 in earth E which is under or adjacent water having a level 14. Apparatus for practicing the present invention includes a floatable hull 16, such as that described in U.S. Pat. Nos. 2,731,741 and 2,944,352, which areincorporated herein by reference. An operators cab, generally designated 11, having an elevated operators compartment 13 is supported on the hull 16. The hull 16 includes a forwardly opening well 18 receiving a forwardly disposed dredge ladder, generally designated 20, pivotally mounted on pivot pins 200 fixed to the hull l6.

For supporting the dredge ladder 20, an A-frame assembly, generally designated 22, is swingably mounted on pivot pins 24 at the front of the hull l6 and is vertically supported by a cable 19 which is fixed to the upper end thereof and is wound on a rotatable hydraulically driven hauling or winch drum unit 21 supported on the front of the hull 16. The A-frame assembly 22 mounts a pulley 26 at its upper end and supports the dredge ladder 20 by means of a cable 28 trained around the pulley 26 and another pulley 30 mounted on a pulley support member 32 fixed to the front end of the dredge ladder 20. As the hydraulic drive unit 21 is alternately rotated in opposite directions, the cable 19 is alternately wound and unwound thereon to respectively raise and lower the A-frame assembly 22 and the dredge ladder 20. At least one support cable 34 is also 3 attached to the apex of the A-frame 22 and extends rearwardly to a spud support frame s at the stern of the hull 16.

Apparatus for selectively advancing the hull 16 forwardly toward the brush l and roots 12 to be removed comprises hinged pairs of spud wells or guides 38, on

I the stern of the hull 16 for receiving a pair of hydraulically vertically reciprocable spuds 40 and 41, respectively, one of which is releasably anchoredin the firm bottom earth E, as illustrated at 50.

A winch 25 is provided on the dredge ladder and includes a pair of drums 46 on which a pair of cables are wound. The cables 44 are trained around idler pulleys 47, fixed to the dredge ladder 20, and are fixed to a pair of laterally spaced apart trees or anchors 49 firmly anchored in firm earth E on opposite sides of the bog. The cables 44 are oppositely wound on the drums 46 such that when one of the cables 44 is wound on one of the drums 46, the other is unwound from the other drum 46. Only one of the spuds 40 and 41 is anchored in the earth E at anyone time so that as the cables 44 are alternately wound and unwound on the drums 46, the hull 16, carrying the dredge ladder 20, will swing about the anchored spud in alternate directions represented by the arrows a and b (FIG. 2).

Rotatably mounted on the front of the dredge ladder 20 is a rotatable, generally hollow, excavating cutterhead, generally designated 52, including a plurality of digging teeth 53 for digging and collecting dirt. A rotatable cutterhead drive shaft 54 is connected with the rotary cutterhead 52 and is driven by a suitable hydraulic motor 56 supported on the ladder 20. A material removing suction pipe 58, having its forward end communicating with the cutterhead 52, is supported on the dredge ladder 20 and is connected at its rearward end to a long, flexible suction sleeve or pipe 60 connected with the inlet side of a primable, dredge suction pump 62 supported on the hull 16. The pump 62 is driven by a suitable Diesel or electric motor 64. An outlet pipe or sleeve 65 is connected to the output side of the pump 62 and delivers the slurry sucked up by the pump 62 to a remote location. The dredge ladder 20 can be lowered sufficiently so that the cutterhead 52 typically lowers to a ZO-foot depth below the surface 14 of the water. Theapparatus which has been described heretofore is fairly representative of prior art constructions and reference may be had to the Schmidt and Milne patents for more information on these constructions.

The dredging apparatus for practicing the invention includes a chipping disc assembly, generally designated 66 and mounted on the front end of a boom 68 which is pivotally mounted aside the dredge ladder 20 on the front of the hull 16 by a pair of pivot pins 69. A pair of double acting, hydraulic cylinders 70 are pivotally mounted on the front of the hull 16 by pivot pins 72 and include piston rods 74 pivotally connected, by pivot pins 76, to the boom 68 rearwardly of the pivot pins 24 so as to vertically swing the boom 68 and chipping wheel assembly 66 between the inoperative positions, illustrated in solid lines in FIG. 1, and the lowered, operative, brush chipping position also illustrated in chain lines in FIG. 1.

The chipping disc assembly 66 includes a shield or shroud 78, fixed to the forward end of the boom 68 and surrounding the upper rear section of a rotary chipping disc 80, which is fixed to a shaft 82 (FIG. 3) pivotally mounted in bearings 84 supported on the shield 78. A

plurality of circumferentially and radially spaced wood and brush cutting or chipping knives, generally designated 86, arranged in spiral formation on one face of the disc for cutting the wood, brush-and trees 10 into small chip fragments. The knives 86 are mounted in axial slots or openings 86a provided in the disc and discharge the chips or fragments in a generally axial direction through the openings 86a in the disc at an angle in the neighborhood of 90 to the extent of the knives 86 (see FIG. 5). As FIGS. 5 8 indicate, each knife 86 comprises a generally U-shaped plate P having its front 'end relieved or beveled to provide an axially inclined face 86b terminating at its forward end in a generally radially disposed cutting edge C. Each knife plate P also includes radially spaced apart, oppositely inclined surfaces 86c which radially and axially diverge and terminate in forward cutting edges C bounding the cutting edge C. The edges C and C' together define a continuous, U-shaped cutting edge. The cutting edges C radially diverge in an axial direction toward the disc 80 and lie in the same generally radial plane as the cutting edge C'. Bolts 86d secure the knives 86 to holders 86e fixed in each opening 86a. The disc 80 is recessed at 86f adjacent each axial opening 86a to receive a portion 86e of the knife holders 862 fixed to the disc 80 by bolts 86g.

Apparatus for driving the chipping disc 80 includes a boom supported fluid operated motor 88, driving a sprocket wheel 90, having a drive chain 92 trained therearound and a sprocket wheel 94 fixed to the chipping disc drive shaft 82. The shield 78 includes a rearwardly flaring deflector shield portion 93 for deflecting the chipped material, sped rearwardly and radially by the chipping wheel 80, in a downward path of travel. The side 93a of the shield 93 remote from the chipping knives 86 is flared laterally outwardly (see FIG. 3) to enhance the lateral deflection of the chipped material toward the cutterhead 52. It should be noted that the planar chipping wheel 80 is inclined relative to a vertical plane at an angle typically about l5 to facilitate the chipping of vertical trees, and longitudinally inclined, also typically about 15 degrees, relative to the longitudinal extent of booms 20 and 68. This enhances bunching of the material to hold it for chipping.

Each of the disc supported cutting knives 86 will always take a cross grain cut whether the tree or the like is vertically disposed or has been cut and is lying on the.

earth and thus breaks the material being cut into small chips. When the trees or brush are vertical, edges C particularly take the cross grain cut, and when lying horizontally on the ground, edges C particularly take the cross grain cut. The spiral arrangement of the knives 86 also reduces the horsepower required to drive chipping disc 80 since only a small radial portion of the total available cutting length of all knives 86 is in position to cut at any one time. Also, when the chipping disc 80 is turning in water, as normally is the case, the knife segments 86 tend to pump the water in which the wood is submerged rearwardly toward the shield 93. The individual knife segments 86 pump substantially less water than would a knife blade having a radial length equal to the length of the individual knife segments 86 and this, of course, also reduces the power requirements of the chipping disc driving motor 88. It should also be noted that the chipping disc 80 is spaced forwardly of the rotary excavating cutterhead 52 so as to reduce all of the brush, trees, and roots 12 to chips and the disc 80 will not have to be lowered below the position shown in chain lines in FIG. I to remove the root system.

. THE OPERATION One of the spuds 40 and 41, for example spud 40, on which the stern of the hull 16 is pivoted, is driven into the earth E while the other is removed from the earth. The winch 25 is then initially operated to swing the hull 16, the cutterhead supporting dredge ladder 20, and

the chipping wheel support boom 68, in the lateral direction represented by the arrow a. As the chipping assembly 66 is swung laterally in the direction of the arrow a, the trees and brush and roots 12 will be forced toward the brush therebehind, which provides backing therefor, permitting the trees and brush to be bunched so that the knives 86 can chip the trees, brush and roots in the path of the chipping disc 80, into small chips or fragments, and direct them axially through the slots 86a and rearwardly to be laterally and downwardly deflected by the shield 93 toward the rearwardly disposed cutterhead 52. I

The dredge ladder and rotary excavating cutterhead 52 are at this time typically initially near the surface'of the water, rather than in the position shown in- FIG. 1, for example, in the positions illustrated in chain lines at 52 in FIG. 1, to remove earth adjacent the surface of the water. The trees and roots which may have been present in the area being dredged by the cutterhead 52 have been previously cut kinto small chips by the chipper wheel 80 and the top layer of earth has been also removed by disc 80, as the chipping wheel 80 always precedes the cutterhead 53 to cut any wood trees, brush or the like into small chips which can beeasily removed by the dredge cutterhead 52 and suction mechanism 60. The cutterhead 52 will remove a swath of earth as it swings in its path of travel represented by the arrow a. When the hull reaches the furthermost lateral position, illustrated in chain lines at 16, the winch is reversed and the hull 16 is swung in the opposite direction represented by the arrow b.

Prior to swinging the hull 16 in a return path, the dredge ladder 20 is lowered so that the cutterhead 52 is in the lowered position illustrated at 52". The chipping assembly 66 is, however, raised from the lowered cutting position, illustrated in chain lines (FIG. 1), to the inoperative position, illustrated in solid lines (FIG. 1), as the cutterhead 52 is swung in the return path of travel represented by the arrow b. When the hull 16 reaches the position illustrated at 16" (FIG. 2) the winch 25 is again reversed to swing the hull in the lateral direction a. Prior to the hull 16 commencing its return in the swinging path of travel a, the dredge ladder 20 is again lowered to move the cutterhead 52 to the position illustrated in solid lines (FIG. 1) to cut another deeper swath of earth which is removed as a slurry through the suction pipes 58, 60 and 65. During the second swinging path a, however, the cutting wheel 80 remains in the raised position illustrated in solid lines (FIG. 1). The dredge ladder 20 can be repeatedly lowered as the winch 25 alternately swings the hull 16 in the to-and-fro path of travel until the earth has been excavatedto the proper depth. Alternatively, it would be possible in some instances to startat the bottom and move upwardly with cutterhead 52.

To advance the dredge forwardly toward the unexcavated bank of earth E, the spud 4i is driven into the bottom 50 when the hull 16 is -in the position 16" and the other spud 40 is removed from the earth. The hull 16 will then swing about the spud 41, which is now in the forwardly advanced position illustrated at 41', and the entire apparatus will be moved forwardly a distance equal to the distance between the spud positions 41 and 41'.

The dredge ladder 20 is raised to a position such that the rotary cutterhead 52 is again in the position illustrated at 52' and the chipping assembly 66 is lowered so that the chipping wheel is in the operative brushcutting position illustrated in chain lines in FIG. 1 and the operation is repeated. The sequence is repeated until a basin, lake, or the like hasbeen fully formed.

It is to be understood that the drawings and descriptive matter are in all cases to be interpreted as merely illustrative of the principles of the invention, rather than as limiting the same in any way, since it is contemplated that various changes may be made in various elements to achieve like results without departing from the spirit of the invention or the scope of the appended claims.

I claim: y

l. A method of enlarging an underwater basin or body of water having an earth bank with chippable material such as brush, trees, roots and the like growing at the bank comprising the steps of:

breaking up and collecting earth material and mixing it with liquid to form a slurry, and then applying forces to the collected earth slurry to remove it to a remote location;

simultaneously forcing the above ground chippable material, such as brush, forwardly toward the above ground material behind it to bunch the chippable material; and

reducing the bunched chippable material to chips and fragments and mixing them with said liquid so that said chippable material is removed with said slurry to said remote location.

2. The method as set forth in claim 1 wherein said breaking and collecting is accomplished by moving a cutterhead in a to-and-fro, generally horizontal, path of travel to dig and collect material to be dredged at various depths; and said chipping is accomplished by moving rotary chipping means, which is rotated about an axis inclined to the horizontal, in a generally horizontal path of travel to reduce trees, roots, brush, and the like growing on the bank to chips and fragments, and then directing the chipped material to a location for removal with said slurry to said remote location.

3. A method of enlarging an underwater basin or body of water having an earth bank with chippable material such as trees, brush, roots, and the like, growing on the bank comprising:

moving a material removing cutterhead in a to-andfro horizontal path of travel to dig and collect material to be dredged at various selected depths; removing said material from said cutterhead in slurry form and transferring it to a remote location;

' deflectingthechipped moving chipping disc means, disposed forwardly of and at a higher levelthan said cutterhead, in a horizontal path of travel to reduce trees, roots, brush, and the like to be dredged to chips and fragments;

and t material expelled by said chipa ping means laterally and downwardly to a location forremoval as a part of said slurry to said remote location. 1 i

; 4.'The method asset forth in claim 3 including the stepof additionally vertically moving said cutterhead independently of said chipping means to locate said cutterhead at various' depths.

5. A method of enlarging an underwater basin or body of water having an earth bank with chippable material such as brush, roots, and trees and the like grow- 8 ing at the bank, comprising:

moving a material collectingand removing dredging element in a to-and-fro, generally horizontal path of travel at various depths; forming a slurry of collected earth and water and transferring it to a remote location; reducing said chippable material to fragments by moving a rotary chipping knife, having cutting edge means, in a horizontal path and presenting said edge means to vertically growing trees such that said trees are cut by said edge means angularly to the vertical plane in which said trees lie when said chipping knife is rotated and moves in said horizontal path; and introducing said fragments to said slurry for removal. 

1. A method of enlarging an underwater basin or body of water havinG an earth bank with chippable material such as brush, trees, roots and the like growing at the bank comprising the steps of: breaking up and collecting earth material and mixing it with liquid to form a slurry, and then applying forces to the collected earth slurry to remove it to a remote location; simultaneously forcing the above ground chippable material, such as brush, forwardly toward the above ground material behind it to bunch the chippable material; and reducing the bunched chippable material to chips and fragments and mixing them with said liquid so that said chippable material is removed with said slurry to said remote location.
 2. The method as set forth in claim 1 wherein said breaking and collecting is accomplished by moving a cutterhead in a to-and-fro, generally horizontal, path of travel to dig and collect material to be dredged at various depths; and said chipping is accomplished by moving rotary chipping means, which is rotated about an axis inclined to the horizontal, in a generally horizontal path of travel to reduce trees, roots, brush, and the like growing on the bank to chips and fragments, and then directing the chipped material to a location for removal with said slurry to said remote location.
 3. A method of enlarging an underwater basin or body of water having an earth bank with chippable material such as trees, brush, roots, and the like, growing on the bank comprising: moving a material removing cutterhead in a to-and-fro horizontal path of travel to dig and collect material to be dredged at various selected depths; removing said material from said cutterhead in slurry form and transferring it to a remote location; moving chipping disc means, disposed forwardly of and at a higher level than said cutterhead, in a horizontal path of travel to reduce trees, roots, brush, and the like to be dredged to chips and fragments; and deflecting the chipped material expelled by said chipping means laterally and downwardly to a location for removal as a part of said slurry to said remote location.
 4. The method as set forth in claim 3 including the step of additionally vertically moving said cutterhead independently of said chipping means to locate said cutterhead at various depths.
 5. A method of enlarging an underwater basin or body of water having an earth bank with chippable material such as brush, roots, and trees and the like growing at the bank, comprising: moving a material collecting and removing dredging element in a to-and-fro, generally horizontal path of travel at various depths; forming a slurry of collected earth and water and transferring it to a remote location; reducing said chippable material to fragments by moving a rotary chipping knife, having cutting edge means, in a horizontal path and presenting said edge means to vertically growing trees such that said trees are cut by said edge means angularly to the vertical plane in which said trees lie when said chipping knife is rotated and moves in said horizontal path; and introducing said fragments to said slurry for removal. 